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Finding the Fourth Proportional to 319.95, 476.89 and 287.55

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Solution

The fourth proportional to 319.95, 476.89 and 287.55 is: 428.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    319.95 : 476.89 = 287.55 : x
  2. Step 2: Convert to fraction form
    319.95/476.89 = 287.55/x
  3. Step 3: Cross multiply
    319.95x = 476.89 × 287.55
  4. Step 4: Simplify right side
    319.95x = 137,129.00
  5. Step 5: Solve for x
    x = 137,129.00/319.95
  6. Step 6: Final answer
    x = 428.60

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.